A throughput of 1 Gbps can be reached with LTE-Advanced technology, which includes a carrier aggregation (CA) technique. In the LTE, frequency bands are numbered and designated as BAND1, BAND2, and so on. For instance, BAND1 corresponds to the 2 GHz band (uplink 1920 to 1980 MHz, downlink 2110 to 2170 MHz). As another example, BAND5 corresponds to the 800 MHz band (uplink 824 to 849 MHz, downlink 869 to 894 MHz). Each frequency band is allocated to a country, a region, and a carrier.
Related techniques are disclosed in Japanese Laid-open Patent Publication Nos. 2002-317942 and 2004-288201.